1. Field of the Invention
The invention relates to an electronically controlled sewing machine and, more particularly, to a technology that makes it possible, by using an informing device, to know which of various basic operations of the sewing machine, including the threading through a needle and the setting of a work cloth to a sewing position, is possible or impossible.
2. Description of the Related Art
Conventional home-use electronically controlled sewing machines provide various practical patterns, such as straight stitching and zigzag stitching; various character patterns, such as Japanese phonetic characters, that is, "hiragana" and "katakana", and Roman letters; and various embroidery patterns including symbols, marks, and images, which are pre-stored in a pattern data memory provided in a ROM (non-volatile memory) of a control unit. A desired pattern or embroidery pattern can be found and selected by a user displaying patterns on a display panel and switching display screens. After selecting a desired pattern, the user simply operates a start switch, so that the sewing machine motor is immediately driven to form the selected pattern in a work cloth.
However, an inexperienced user who has just bought an electronically controlled sewing machine may well be unfamiliar with the names of parts, such as "presser foot" and "thread take-up lever", and also unfamiliar with various basic operations involved in using a sewing machine, such as the needle thread placement, bobbin thread preparation, and bobbin replacement. A latest-model electronically controlled sewing machine is equipped with many functions, so that the handling of the machine is complicated. Therefore, when a user who has just bought an electronically controlled sewing machine actually performs an action such as needle thread placement or bobbin thread preparation, the user needs to frequently refer to the instruction manual to follow the described procedures step by step and thereby manage to place the needle thread at designated positions, to wind a thread around a bobbin, set the bobbin in a bobbin case, and mount it in the shuttle body.
After the needle thread and the bobbin thread have been made ready, a desired stitching pattern must be selected. Actual stitching will be started only after the user performs further operations, for example, raises the presser foot, inserts a work cloth between the presser foot and the needle plate, lowers the presser foot onto the work cloth, and then operates the stitching start switch. To perform these operations, too, the user may well have to keep the instruction manual nearby and to refer to the described procedures step by step.
As stated above, a user unfamiliar with the names of the parts of a sewing machine and the basic operations to use the machine is often uncertain whether, for example, it is possible to place a needle thread at the designated positions or to pass the needle thread through the needle eye, with the needle bar and the thread take-up lever being at the present positions, or whether it is possible to replace the bobbin shuttle. However, the sewing machine itself does not indicate or display any information regarding whether it is possible to perform a basic operation as mentioned above. As a result, the user may possibly look at the instruction manual again and again and/or perform the operations by trial and error. Moreover, knowing that the sewing machine is "electronically controlled" may add to the inexperienced user's uncertainty about things that the user sees or performs.